Apparatus for making briquettes



Oct. 20, 1931 H. ARCHBALD 1,828,586

APPARATUS FOR MAKING BRIQUETTES Filed May 14, 5

Patented Oct. 20, 1931 UNITED STATES HUGH ABCHBALD, OF PHILIPSBUBG, PENNSYLVANIA APPARATUS FOR MAKING 'BRIQUETTES Application filed Kay 14, 1925. Serial No. 30,843.

The present invention has for its object the production of coal briquettes from materials which, at the present time, constitute either waste products, or products which bring only 6 a very small price upon the market.

A further object of the present invention resides in the production of briquettes of the character described by a new and improved apparatus.

I 10. Part of the subject matter found in this proportion of coal dust and small sizes are converted into briquettes.

ploy coke, produced in situ and of a relatively high mechanical strength, as the binder, for b1nding the particles of anthracite coal together.

It is referable to produce the said coke from co ing bituminous coal which is thoroughly mixed with the anthracite dust, and to employ a temporary binder for aiding in forming the shape, and for holding said shape I durin the heating operation during which theco e (permanentbinder) isformed. The preferred temporary binder is heavy mineral oil material.

In carrying out the process, I preferably mix the three essential constltuents of the mixture together, namely (a) anthracite coal dust and small sizes, which form the bulk or basis of the mixture, (6) a bituminous coal of a readily coking character, which material is substantially acted upon by heavy mineral oils alone or mixed with heavy tar oils and (c) an oily material of the character mentioned.

I call attention to the fact that I preferably do not use a pitchy material as the temporary For producing briquettes, I preferably em binder, and the oils which I prefer to use are those which are relatively low in pitchy material, if any pitchy material is present. The oil may or may not leave a coky residue on heating to a high temperature.

The mineral oil preferably used, which forms the preferred oily material to use in the process, is the still bottoms of petroleum, after distilling off the gasoline and kerosene and other relatively volatile fractions, relatively free from pitch or pitchy material, and gives very much better results than the use of pitchy materials.

The desired" properties of the final coal briquettes are that the same should burn without the production of any substantial odor, smoke or soot. The briquettes should be comparable with anthracite coal in these respects, and should of course be of sufficient hardness to burn to an ash, without first falling to a powder or into a mushy or semi-liquid or pasty state.

In accordance with the present inventlon, the coking coal (bituminous coal) is first ground to a fine powder, so that it will pass a screen having about 100 to 200 meshes per linear inch,-fine grinding making a stronger coked briquette. The bituminous coal and the anthracite coal dust or small sizes are mixed together in a dry state, that is to say, con- 8 taiping a sufficiently low moisture content to enable the mass to readiliy be poured as a powder in order to .avoid 'sagreeable evolution of steam during the heating 0 eration. It is advisable to first dry the coal, 0th the hard coal andthe soft coal and this 0 eration may conveniently be erformed whi ethe two kinds of coal are entlrely separate from each other, i. e. before mixing together. Thisis particularly the case in using coal dust coming from a wet breaker or washer, or wet coal dust coming from a culm bank during the rainy season. While the dust of anthracite coal may be used I prefer to use the small sizes. When the lattenare used they appear in the finished briquette more or less in liheiroriginal shape cemented together by co e.

The proportions will vary substantially,

thus for instance one partof oil, three parts of bituminous coal and six parts of anthracite coal, producing hard and strong briquettes, while one-half part of oil, two and one-half parts of bituminous coal and seven parts of anthracite coal producing a briquette strong enough for use in some conditions, but materially weaker than those produced in the preferred example.

The three materials are preferably mixed together, in the proportions above stated, and it is advisable to mix the same as thoroughly as possible, in order that the heavy mineral oil may act upon the bituminous coal, to convert the same into a more or less gummy mass. The heavy oil used may insome cases have a coke residue, although this is not necessary.

After thoroughly mixing the oil, coking coal and anthracite coal the mixture is formed into finished briquettes by means of my improved apparatus and process. Broadly stated the process comprises the steps of forcing the mixture through a heated tubular or like member and subsequently further heating the compacted mixture. While various forms of apparatus may be devised for carrying out my process I have found the one described herein is particularly desirable and useful and it also forms partof invention.

m Tn the drawings accompanying this description, wherein like numerals refer to corresponding parts, Fi 1 is a longitudinal section of the improved apparatus and Fig. 2 is a cross-section on the line 11-11 of Fig. 1.

The hopper into which the mixture of anthracite coal, bituminous coal and mineral oil is introduced is designated b. the numeral 1. The material fed into the opper is advanced through the heated tube 2 by means of the screw conveyor 3, or other suitable conveying or advancing means, driven by a suit able source of power connected with gear 4 operatively connected with the conveyor. The conveyor 3, at its end, carries a projecting stem 5 which produces a central opening in the mixture as it is advanced through the heated tube 2. This central opening is retained. by the heated mass throughout its larged travel through the tube2 and occurs also in the final product. The conveyor is su ported in the tube 2 and is journalled in t e end 17 thereof and in bracket 18.

The screw conveyor 3 is mounted in an enpart a of the tube 2 preferably outside of the casing 9 hereafter described and this enlarged part may be integral with the remainder of the tube 2 or it may be formed as a separate art and attached to the tube 2 by suitable astening or connectin means. The tube 2 may be formed of meta capable of resisting the temperature produced within the casing 9 hereinafter described. At 6 there is shown a constriction or abutment in the part a of tube 2, or in the tube .2 it-' rounded, the exhaust gases being discharged through the stack 20. Bafiies 10 cause the hot gases arising from the furnace 6 to distribute themselves uniformly around the tube, insuring uniform heating. The baflie 10 on the under side of the tube 2 performs the additional function of supporting the central part of the tube 2 which is also supported at its two ends by the casing 9 and the wall 14' of the chamber 14. The number of baffles may be increased over the number shown depending upon the length and size of the casing 9.

As the material emerges from the end of. the tube 2 adjacent the cutters 11, mounted in the chamber 14, it is cut into convenient lengths. The adz' shaped cutters 11 are carried on arms 12 suitably mounted on a shaft 13 rotated by any convenient means. The lengths of the tubular mixture emerging from the tube 2 produced by the cutters 11 will obviously be determined by the rate of rotation of the cutters 11 and the rate the ma- 100 terial is forced through the tube 2.

The parts of partly coked mixture produced by the cutters 11 are of the general shape of the final briquette product, but in order to complete the coking and complete the formation of the briquettes they are subjected to an additional heat treatment in chamber 14. A shaped and partly coked briquette undergoing final treatment is shown at 21, the numeral 22 denoting the central opening produced by the stem 5 of the conveyor 3. The heated briquettes are allowed to accumulate in the chamber 14 until, for example, almost half full and are given their final heat or coking treatment in this chamber by heat derived from external means as from the furnace 6, as described, either alone or in combination with internal heating of the mass by a slight combustion of the material of the bri uettes by air purposely admitted through t e valve 15, or accidentally. leaking past it when closed, due to im erfections in the valve itself, or admitte when the valve 15 is operated to discharge the finished briquettes. The air thus admitted flows upwardly through the mass of briquettes combining with a slight part of the material thereof, and the products of this combination or combustion together with the products of distillation from the partly coked briquettes pass out of the chamber 14through the conduit 17, since the chamber 14 is separate from the furnace ,6 and the chamber 9. The flow of air is prevented from entering or leaving the tube 2 by the advancing material therein. The products passing out the conduit 17 may be subjected to suitable con (lensing and washing operations in order to recover condensable volatile constituents thereof and gaseous fuels. The condensable constituents or oils in certain instances may be used in forming the mixture to be treated, while the gaseous fuels may be consumed in the furnace 6. Other applications of the byproducts may be made.

The finished briquettes are withdrawn continuously, or intermittently at convenient intervals, from the outlet 16 at the lower part of the chamber 14 in such amounts as to substantially retain the top level of the material in the chamber 14 below the cutters 11 and preferably midway between the too ofthe chamber and the lowermost point of the material.

It is advisable to have the top level of the briquettes in chamber 14 at such a point as to aiford only a slight fall of the partly vcompleted briquette from the cutters 11, so that the briquettes are not broken unnecessarily.

The material while passing through the tube 2 shouldpreferably be subjected to a high enough temperature. to hold it in a tubelike shape, while the temperature of the material within the chamber 14 should preferably be carried up to about 550 C. or to such a temperature as will accomplish low temperature distillation of the carbonaceous ma- .terial. The material passing through the The parts of'the apparatus subjected t o heat may be formed of suitable metal, brick or masonry or a combination of these materials. In constructing the above apparatus.

it has been found desirable, in order to in- 'crease the output of briquettes, to arrange a plurality of tubes 2 in parallel in a horizontal, vertical or inclined plane.

- Having described my invention what I claim is:

A briquette forming apparatus comprising a passage, a chamber surrounding said passage, a furnace connected with said chamber means for feeding briquette forming material through said passage from one end thereof to the other end thereof, a coking chamber for receiving the discharge from said passage, and means adjacent said other end for severing the discharge from said passage.

In testimony whereof I aflix my signature.

HUGH ARGHBALD. 

